(2E)-1-(5-Chloro-thio-phen-2-yl)-3-(2,3-dimeth-oxy-phen-yl)prop-2-en-1-one

In the title compound, C₁₅H₁₃ClO₃S, the chloro­thio­phene and dimeth­oxy­phenyl groups are linked by a prop-2-en-1-one group. The C=C double bond exhibits an E conformation. The mol­ecule is non-planar, with a dihedral angle of 31.12 (5)° between the chloro­thio­phene and dimeth­oxy­phenyl rings. The meth­oxy group at position 3 is coplanar with the benzene ring to which it is attached, with a C—O—C—C torsion angle of −3.8 (3)°. The meth­oxy group attached at position 2 of the benzene ring is in a (+)synclinal conformation, as indicated by the C—O—C—C torsion angle of −73.6 (2)°. In the crystal, two different C—H⋯O inter­molecular inter­actions generate chains of mol­ecules extending along the b axis.

(2E)-1-(5-Chloro-thio-phen-2-yl)-3-(2,4,5-trimeth-oxy-phen-yl)prop-2-en-1-one

In the title mol­ecule, C₁₆H₁₅ClO₄S, the chloro­thio­phene and trimeth­oxy­phenyl rings make a dihedral angle of 31.12 (5)°. The C=C double bond exhibits an E conformation. In the crystal, C—H⋯O inter­actions generate bifurcated bonds, linking the mol­ecules into chains along the b axis.

4-Azido-methyl-7-methyl-2-oxo-2H-chromene-6-sulfonyl azide

In the title compound, C₁₁H₈N₆O₄S, the plane of the coumarin aromatic ring is twisted by 17.2 (2)° with respect to the plane of the azide group bound to the methyl­ene substituent, whereas it is twisted by 83.2 (2)° to the plane of the azide attached to the sulfonyl group. The crystal structure is stabilized by weak C—H⋯O inter­actions, leading to the formation of dimers with R₂²(12) graph-set motifs. These dimers are further linked by weak S—O⋯π and π–π contacts [centroid–centroid distance = 3.765 (2) Å], leading to the formation of a layered structure.

In situ surface modification of molybdenum-doped organic-inorganic hybrid TiO2 nanoparticles under hydrothermal conditions and treatment of pharmaceutical effluent

Molybdenum-doped TiO2 organic-inorganic hybrid nanoparticles were synthesized under mild hydrothermal conditions by in situ surface modification using n-butylamine. This was carried out at 150 degrees C at autogeneous pressure over 18 h. n-Butylamine was selected as a surfactant since it produced nanoparticles of the desired size and shape. The products were characterized using powder X-ray diffraction, Fourier transform infrared spectrometry, dynamic light-scattering spectroscopy, UV-Vis spectroscopy and transmission electron microscopy. Chemical oxygen demand was estimated in order to determine the photodegradation efficiency of the molybdenum-doped TiO2 hybrid nanoparticles in the treatment of pharmaceutical effluents. It was found that molybdenum-doped TiO2 hybrid nanoparticles showed higher photocatalytic efficiency than untreated TiO2 nanoparticles.

N-H...F hydrogen bonds in fluorinated benzanilides: NMR and DFT study

Using (19)F and (1)H-NMR (with (14)N decoupling) spectroscopic techniques together with density functional theoretical (DFT) calculations, we have investigated weak molecular interactions in isomeric fluorinated benzanilides. Simultaneous presence of through space nuclear spin-spin couplings ((1h)J(N-HF)) of diverse strengths and feeble structural fluctuations are detected as a function of site specific substitution of fluorine atoms within the basic identical molecular framework. The transfer of hydrogen bonding interaction energies through space is established by perturbing their strengths and monitoring the effect on NMR parameters. Multiple quantum (MQ) excitation, up to the highest possible MQ orders of coupled protons, is utilized as a tool for accurate (1)H assignments. Results of NMR studies and DFT calculations are compared with the relevant structural parameters taken from single crystal X-ray diffraction studies.

Synthesis, characterization, and crystallographic study of the PbO-Bi2O3-V2O5 system: Pb(3-x)Bi(2x/3)V2O8 (0.20 < or = x < or = 0.50)

A new solid solution Pb(3-x)Bi(2x/3)V(2)O(8) (0.20 < or = x < or = 0.50), stabilizing the high-temperature gamma form of Pb(3)V(2)O(8), has been isolated in the system Pb(3)V(2)O(8)-BiVO(4). The single-crystal structure of the composition x = 0.50 (Pb(2.5)Bi(1/3)V(2)O(8)) was solved using single-crystal X-ray diffraction (XRD) technique. The compound crystallizes in the trigonal crystal system R3m (No. 166) with a palmierite structural type with a = 5.7463(3) A, c = 20.3047(12) A, V = 580.64(5) A(3), and Z = 3. The final R1 value of 0.0406 was achieved for 217 independent reflections during the structure refinement. The variable-temperature powder XRD shows the absence of any phase transition for all of the members of the solid solution in the limit of 398-80 K. The new solid solution has been characterized by neutron powder diffraction, solid-state UV-vis diffuse-reflectance spectra, scanning electron microscopy, and X-ray photoelectron spectroscopy (XPS). Alternating-current impedance studies indicate conductivity on the order of 10(-4) Omega(-1) cm(-1) for Pb(2.5)Bi(1/3)V(2)O(8). The change in color of the samples from brown to yellow at high temperature was explained by XPS studies, which indicate the plausible formation of the ppm level of Bi(2)O(3) at such elevated temperature ranges.

Thiourea based novel chromogenic sensor for selective detection of fluoride and cyanide anions in organic and aqueous media

Novel chromogenic thiourea based sensors 4,4'-bis-[3-(4-nitrophenyl) thiourea] diphenyl ether 1 and 4,4'-bis-[3-(4-nitrophenyl) thiourea] diphenyl methane 2 having nitrophenyl group as signaling unit have been synthesized and characterized by spectroscopic techniques and X-ray crystallography. The both sensors show visual detection, UV-vis and NMR spectral changes in presence of fluoride and cyanide anions in organic solvent as well as in aqueous medium. The absorption spectra indicated the formation of complex between host and guest is in 1:2 stoichiometric ratios.